The Statistics, Measurement &Data Management (SMDM) Core will centrally unify the proposedprogram project serving all four proposed research projects by providing the data management backbone, building comparable cohorts, working with project investigators to construct and test independent and dependent variables that are conceptually and theoretically appropriate to project hypotheses, conducting analyses, and assembling materials for dissemination. Specifically, this core will: 1. Assemble project data, and develop methods for tracking and cleaning of projects'longitudinal data: a. Construct cleaned, multi-level linked databases from MDS, Medicare claims, OSCAR, ARF, Dartmouth Atlas, state survey, other publishedpolicy sources andprovider surveys; b. Update and expand longitudinal data cleaning of provider survey certification data (OSCAR); c. Incorporate information from part B claims into Brown's Residential History File patient tracking system and improve tracking algorithm. 2. Create uniform, theoretically consistent core measures. a. Create measures from multiple data sources to characterize state policies, markets, provider behavior andperformance, patient case-mix andpatient outcomes for all participating projects; b. Identify published quantitative and qualitative data (provider, market and state policy data) on the LTC environment in the U.S, coding and including relevant information into the PPGdata base; 3. Construct analytic files and conduct analyses for all projects using appropriate statistical approaches. 4. Develop new statistical methods and market measures required for all PO1 studies: a. Undertake specialized studies of LTC market definitions, and characterize and compare the resulting descriptions of LTC markets for use in the Program Project studies; b. Develop new statistical methods to handle cross-classified data structures such as different markets in which a LTC provider is situated, and the effects of changing market characteristics; c. Develop statistical models that provide population average estimates within a multilevel context; d. Develop statistical methods to estimate direct, indirect and total effects in the mediating models. 5. Disseminate data, measures, and statistical methods developed in this project under guidance of Core A Lay Summary: This project involves multiple and complex data sets that must be merged and analyzed. The Statistics, Measurement &Data Management core creates appropriate designs, measures and analysis plans and assures that the data are appropriately analyzed, interpreted, and disseminated.